Water PollutionBy Table 4

North Carolina’s Bay of Pigs• “There was more Pigs than People!”-- Victoria

Matthews• North Carolina # 2 state in pig farming nation• Hurricane Floyd caused extreme flooding in North

Carolina September 1999• Unusual • Water contained thousands of dead pigs• Feces and Urine from pigs• Pig waste flooded creeks rivers and wetlands

• Due to the large number of pigs, the state allowed for confining farm housing containing thousands of pigs • Most of the houses were built on floodplains

• Pig waste, about 20 million tons per year, were dumped into unlined lagoons the size of a football field

Affects of Bay of Pigs• Asked the government for $1 billion grant to

repair and replace pig facilities and exemption from the Clean Water act for a few months

• Not allowed• “Hog Roundtable” coalition of civic, health and

environmental groups w/objective of controlling industrial-scale pig farming

• 2004 resulted in a mandate to phase out pig waste lagoons and expand regulations to require buffers

Vocabulary• Pollutant: any biological, physical or chemical substance

that, in an identifiable excess is known to harmful to other living organisms.

• Biochemical oxygen demand (BOD): The amount of oxygen required for biochemical decomposition processes. It is commonly used in water quality management.

• Fecal coliform bacteria: A standard measure and indicator of disease. When this is present in water it indicates that fecal material from mammals or birds is present, so organisms that cause waterborne diseases may be present as well.

• Outbreaks: sudden occurrences

22.1 Water Pollution• Water pollution refers to degradation of water quality • Intended use of water & how far water departs from the

norm in effects of public health, or ecological impacts• Water pollutants have heavy metals, sediment, certain

radioactive isotopes, heat, fecal coliform bacteria, phosphorus, nitrogen, sodium, pathogenic bacteria and viruses.

• Primary Water Pollution Problem: lack of clean water for drinking causing epidemics (e.g. cholera)

• Not global (e.g. epidemic South America)• No insecticides, pesticides, pathogens, and heavy metal

concentrations for consumption• More than ¼ of drinking water systems in U.S. has violated

federal drinking standards

22.2 Biochemical Oxygen Demand (BOD)

• Living life forms need oxygen to breath. When that oxygen is depleted or diluted due to pollutants, life forms cease to live.

• Bacteria in streams cause dead organic matter to decay. If there is enough activity, the oxygen in the water goes below feasible levels.

• Biochemical oxygen demand or BOD is the amount of oxygen required for biochemical decomposition. • Produced by dead organic matter• Added to streams by natural sources• 33% - agricultural practices• Urban old sewer systems (sewage + storm water runoff)

• Used in water quality management• Measures oxygen consumed by tiny microorganisms as they break

down organic matter

22.2 Biochemical Oxygen Demand (BOD)• High flow – sewage plants unable to handle total volume of

water• Gunk overflows untreated into rivers• BOD too low for fishies• Less than 5mg/l of water

• Three zones of high sewage1. Pollution zone• High BOD • Oxygen used up by microorganisms

2. Active decomposition zone• Dissolved oxy reach min• Organic waste transported downstream

3. Recovery zone• Dissolved oxy increase while BOD reduce• Natural stream process replenish water with dissolved oxy

Fishies!!!High dissolved

oxygen High BOD

22.3 Waterborne Disease• Cholera: serious waterborne disease• Cholera epidemic in South America in 1990s• Outbreak in Milwaukee, Wisconsin

• Largest outbreak in U.S. in April 1993• Cryptosporidiosis : gastrointestinal illness carried Cryptosporidium

(microorganism resistant to chlorination) • About 100 people died• Source remained unknown

• Cryptosporidium present 65% to 97%• Another outbreak in Las Vegas in May 1994

• Fecal coliform bacteria• Escherichia coli (E. coli)• Harmful• Outbreak in a water park in Georgia in July 1998

22.3 Waterborne Disease• Outbreak of E. coli bacteria in Walkerton, Ontario,

Canada in May 2000• Caused by cow manure washed into water supply during

rains & flooding on May 12, 2000• Local public utility commission knew on May 18, but did

not report to health authorities• May 26, 5 people died, 20 intensive care, 500 ill

w/cramps, vomiting & diarrhea • Could have been prevented if the Government of Ontario

did not cut back on levels of testing of public water supply